The partial specific volumes of a number of proteins and polypeptides in buoyant CsCl solutions as a function of pH will be measured. The buoyant titrations of an unusual glycoprotein and malic dehydrogenase from halophilic bacteria from the Dead Sea will be determined. The unusual buoyant behavior of poly-Gly, poly-L-Ala and poly-L-Arg will be explored further. Our work on synthetic polypeptides will be extended to buoyant studies of hydrophobic homopolypeptides and sequential co-polypeptides. Specific chemical modifications of several proteins and polypeptides will be made and the resulting polymers studied in density gradients. Density gradient proportionality constants for additional 1:2 and 1:3 salt systems will be computed and thermodynamic data obtained for CsCl at 5 degrees C.